Chennai, May 13: Karunanidhi has belied his name and shown little daya, robbing Manmohan Singh of one of his most dynamic ministers.

Dayanidhi Maran, the communication and information technology minister, resigned tonight after the DMK activated the process for his removal in retaliation for a succession survey that ignited a carnage last week.

The party passed a resolution authorising M. Karunanidhi to act against his great-nephew, three days after the flare-up killed three people in Madurai.

The violence erupted after a newspaper controlled by the Maran family published an opinion poll that put Karunanidhi’s younger son Stalin far ahead of elder brother Azhagiri in the succession race.

Initially, it was assumed that sibling rivalry was behind the conflagration blamed on Azhagiri’s supporters. Later, the party began to feel that the survey could have been published to drive a wedge between Karunanidhi’s sons.

As the paper is run by the Maran family and the first part of the survey had projected Dayanidhi as the most efficient minister from the state, the DMK’s suspicion fell on him.

In the resolution, the DMK has not linked Dayanidhi to the survey. It said: “His (Dayanidhi’s) recent approaches and activities are tantamount to ruining party discipline.” An expulsion notice will also be issued.

Dayanidhi, who is holidaying in Ooty, faxed the resignation letter to the Prime Minister’s Office late tonight after speaking to Manmohan.

In a statement, Dayanidhi said he had not “even thought of betraying Karunanidhi or the party”.

“I will not even think on those lines till I am alive. I have been brought up like that by my grandfather Karunanidhi and my father Murasoli Maran,” he added.

The young Dayanidhi — he is 39 — is credited with driving down long-distance phone rates and making it possible to make a call from Kanyakumari to Kashmir for Re 1.

Manmohan is known to value the efficiency of Dayanidhi but the Prime Minister is unlikely to antagonise Karunanidhi, whose 15 MPs constitute the second-largest group in the coalition.

The Prime Minister had reportedly requested Karunanidhi not to unsettle the central team when they met in Chennai on Friday during the celebrations to mark the DMK leader’s 50 years in the Assembly — an event Dayanidhi did not attend. But intense pressure from his family appears to have forced Karunanidhi’s hand.

Dayanidhi’s departure will leave a vacuum at the telecom ministry. The minister had put what used to be a controversy-prone ministry in order through a mix of reform-friendly measures and tough talk when it came to persuading companies to meet rural obligations.

If Karunanidhi dips into his current reserve of MPs, he will find it hard to get a replacement who can match Dayanidhi’s charisma. The senior-most MP is C. Kuppusamy, who is not in good health.

Dayanidhi is also known for bringing to Tamil Nadu telecom investments, which the DMK credited today to the state government under Karunanidhi’s leadership.